For one thing, it seems you have chosen to be a Sword & Board Fighter which does not have a lot of feat support for added damage. You didn't even take the Dueling Fighting Style. Sentinel would be a good feat for you giving you a way to attack with your reaction. Shield Master can set you up to have advantage on some of your attacks. If you REALLY want more damage, drop the shield and take Polearm master or GWM and get your self a greatsword or greataxe.
As mentioned above, the DPR from the rest of your party is way off from what it should be. The Rogue only has 4d6 sneak damage. Even if it crit every round, it would only be a little over half of that much DPR.
If the Barb uses a Greataxe, and crits every attack(3 at most), it would only be able to deal 6d12(42 damage) + Str, rage damage(+2), and magic bonus damage. Let's assume his Str is 20 and has a +2 magic weapon. That's 27 more damage for 42+27= 69 damage total. Now we can add GWM feat for 30 more damage. That brings it to 99 damage per turn with a lot of assumptions. (Frenzy Barb, GWM, +2 Greataxe, every hit is a crit, etc...)
Your AC is bonkers high. You basically have a +3 magic shield which is seriously broken and should be considered a legendary item as far as I'm concerned.